\begin{tikzpicture}
    \tkzDefPoints{0/0/A, 3/0/B, 4/2/C, 2/2/D, -0.5/2/E}

    \tkzDrawPolygon(A,B,C)
    \tkzDrawPolygon(A,B,D)
    \tkzDrawPolygon(A,B,E)
    \tkzDrawSegments[dashed](C,E)
    \tkzLabelPoints[above](C,D,E)
    \tkzLabelPoints[below](A,B)
\end{tikzpicture}

